Hydrostatic bearing for monitors

ABSTRACT

The invention relates to a monitor for ejecting jets of water, foam or mist, comprising a pipe system attached to a foot support, which is rotatable on the support. The foot support is characterized by a lower disc-shaped part (10), an upper part (13), which is rotatable with respect to the lower part (10), and a fastening ring (15) which presses a flange (14) of the upper part (13) against the lower part (10). The invention consists of arranging through-holes in the upper part (13) from the central hole to the gap between the fastening ring (15) and the flange (14). A hydrostatic bearing between the flange (14) and the fastening ring (15) has been brought about so that the flange and the upper part (13) can be easily rotated.

FIELD OF THE INVENTION

The present invention relates to a monitor for ejecting extinguishingagents towards fires, such as water, foam or mist jets. The inventionrelates more particularly to a foot support carrying the monitor.

PRIOR ART

Monitors for fighting fires are already known. They mainly consist of apipe system which is mounted on a foot plate, through which water orother fire-fighting agents can flow into the pipe system, and acontrollable nozzle which can be directed towards the fire to be fought.The nozzle itself together with its pipe is usually adjustable around ahorizontal shaft, whereas the whole monitor is rotatable around avertical shaft in the foot support. In this way the nozzle can bedirected, within certain limits, towards a randomly chosen target.

Monitors are available in different sizes and for different pressures ofthe through-flowing liquid. One example of such a water pressure is 16bar. The capacity of a monitor having this pressure may be up to 40.000liters/minute.

The liquid which is to be ejected through the monitor is usually water,whereby a normal water jet is obtained which, however, by means of aplate in the nozzle, may be formed into droplets or mist. If foam agentsare added to the water an ejection of foam is achieved.

Monitors of the aforementioned type are usually used on oil rigs or thelike and they have been anchored in strategic positions and can be usedquickly.

THE TECHNICAL PROBLEM

Water cannons according to the prior art work satisfactorily per se.Through the high water pressure which must be brought about in thesewater monitors a high tension however arises in the pipe system, whichmakes it necessary to arrange a thrust bearing in the rotatable area fortaking up these forces. This first bearing may be a standard ballbearing, or ball tracks may be formed directly in the rotatable partswhich are facing each other and filled with balls. To make a bearing ofthis type means an extra cost which is unnecessary as the rotatingmovements are not large or do not occur often. In an environment, forexample on an oil rig, where salt water often splashes over themonitors, the bearings also have to be effectively protected againstrusting solid.

THE SOLUTION

It has therefore long been desired to simplify and make bearings forsuch monitors cheaper and more reliable and one has therefore, accordingto the invention, arrived at a monitor for ejecting jets of water, foamor mist, comprising a foot support consisting of a lower disco-shapedpart having a central through-hole and an upper rotatable part having acentral through-hole concentric with the hole in the lower part and aring attached to the lower part which rotatably connects the upper partto the lower part, and a pipe arrangement carrying the ejecting nozzleattached around the hole in the upper part of the foot support,characterized in that the upper rotatable part comprises an annularflange around the hole which extends outwardly and which is arrangedbetween the lower disc-shaped part and the ring, whereby through-holesare arranged from the central hole in the upper part to the side of theflange which faces the ring so that, in operation, during ejection ofthe liquid when this is subjected to pressure in the central hole, itwill flow from the central hole into the space between the flange andthe ring and thereby form a hydrostatic bearing.

According to the invention it is suitable if sealing rings are arrangedfor sealing the hydrostatic bearing from the surroundings.

It is also suitable, according to the invention, that a seal is arrangedaround the lower part of the upper part for preventing water fromflowing in between the lower part and the rotatable flange.

The ring which connects the upper part is, according to the invention,suitably screwed to the lower part.

Screws are arranged, according to the invention, on the lower side ofthe lower part for screwing to a base.

DESCRIPTION OF THE FIGURES

The invention will in the following be described more in detail withreference to the attached drawings in which,

FIG. 1 shows a monitor seen from the side,

FIG. 2 shows the same monitor seen from above and where

FIG. 3 shows a section of the foot support of a monitor according to thepresent invention.

DETAILED DESCRIPTION

FIG. 1 shows a monitor with a foot support 1 on which pipe system 2 isarranged, said pipe system forming the monitor itself. The pipe system 2has a protruding pipe 3, which is passed over a flange in the footsupport 1. The attachment of the pipe part 3 to the foot support 1occurs suitably by means of screws. The pipe system 2 ends in a nozzle 4which can be directed up or down by means of a handle 5. It is pivotablearound two rings 6.

FIG. 2 shows the same monitor as that according to FIG. 1 above and thesame reference numerals are valid also for this figure. The handle 7which has the object of pulling the nozzle 4 back and forth is seen as aprotruding ball attached to the nozzle 4. The same type of handles 8 areattached to either side of the pipe system and they have the object toswing the monitor around a vertical shaft. Instead of these handles 8 anelectric motor which drives a cog wheel or the like may be arranged in asuitable location. If so it will be applicable for larger dimensions.

FIG. 3 which is a vertical section through the foot support 1, shows alower disc-shaped part 10 having a central through-hole 11. Thisdisc-shaped lower part 10 is provided with a suitable number of screws12 for screwing to a support.

The figure further shows an upper part 13 which is also provided with acentral through-hole concentric with the through-hole 11 in the lowerpart 10. This upper part 13 comprises an annular flange 14 directedoutwardly and being locked between a fastening ring 15 and the lowerpart 10, by means of a number of screws 16. The flange 14 should,however, not be locked in such a way that it cannot be moved. Around thepipe-shaped part of the upright upper part 13, the pipe system in themonitor should namely be fastened and the flange 14 must therefore bemovable so that the monitor can be rotated. To fasten the pipe systemscrews which are screwed from the inside may be used suitably.

In the hole in the upper part 13 preferably four through-holes 17 havebeen made which end in the border surface between the flange 14 andfastening ring 15. When liquid of high pressure is present in theconcentric holes, water will therefore be forced out via thethrough-holes 17 into the gap between the flange 14 and the fasteningring 15. To prevent the water from flowing out and to maintain the waterpressure, seals 18 have therefore been provided. A pressureapproximately corresponding to the pressure in the central hole willtherefore be built up between the flange 14 and the ring 15. Thispressure will counteract the tensioning force upwardly which is presentin the upper part 13 due to the pressure and the fluid pressure betweenthese surfaces will therefore function as a hydrostatic bearing, whichmakes the flange easily movable compared to the ring 15. The other sideof the flange 14 which abutts the lower disc shaped part 10 will, due tothe tensioning force, be lifted up from the disc 10 and no substantialfriction will therefore occur when the water pressure is applied. Toprevent a water pressure being built up at this side and to preventwater leakage, this side of the flange has also been provided with aseal 19, suitably in the shape of an O-ring.

Through the present invention a bearing for a monitor has been broughtabout which, as soon as the water pressure is supplied, will function ina smooth and frictionless manner. Due to the simplicity of the bearinggreat savings are brought about in the manufacturing.

The invention is not limited to the embodiment shown but can be variedin different ways within the scope of the claims.

I claim:
 1. A monitor for ejecting fluids comprising:a lower part havingan upper surface, said lower part having a central through-hole for thepassage of fluids; a upper rotatable part having a central through-holeconcentric with said through-hole of said lower part, said upperrotatable part including an annular flange; an ejection nozzle assemblyoperatively connected to said upper rotatable part about saidthrough-hole of said upper rotatable part; a ring for rotatablyconnecting said upper rotatable part to said lower part, said ring beingattached to said upper surface of said lower part and arranged so thatsaid annular flange of said upper rotatable part is disposed betweensaid ring and said lower part and an annular space is formed betweensaid ring and said annular flange; and at least one flow openingproviding fluid communication between said central through-hole in saidupper rotatable part and said annular space, whereby in operation duringejection of fluids, said fluid will flow from said central through-holeinto said annular space to form a hydrostatic bearing.
 2. The monitor asclaimed in claim 1 wherein a seal is provided between said upperrotatable part and said annular flange to prevent water from flowing outof said annular space.
 3. The monitor as claimed in claim 2 wherein saidseal comprises a plurality of sealing rings for said annular spacebetween said upper rotatable part and said annular flange to preventwater from flowing out of the hydrostatic bearing, said sealing ringsincluding spaced first and second sealing rings arranged to seal theradially inner and outer portions of said annular space.
 4. The monitoras claimed in claim 2 wherein a seal is provided between said lower partand said annular flange to prevent water leakage.
 5. The monitor asclaimed in claim 1 wherein said ring is attached to said lower part byscrews.
 6. The monitor as claimed in claim 1 further including a supportfor mounting of said monitor, and wherein said lower part is attached tosaid support by screws.